Prosthetic work, such as crowns or bridges, for example, requires a supportive substructure in many cases to ensure mechanical stability. Typically, these subframes consist of metal alloys or of metal-free materials such as, by way of example, ZrO2, Al2O3, or high-performance polymers such as PEEK. In order to impart an aesthetic appearance to the tooth restoration on such a subframe structure, the same is given a veneer of a dental composite in the color of the tooth; or in the case of metal subframes, a tooth-colored ceramic. An adhesive agent is typically used to ensure a durable bond.
First, the surface is mechanically treated, typically by means of sand jets. An adhesive layer is then applied first to the sand-blasted subframe, and said adhesive layer produces a bond between the subframe surface and the subsequent (meth-) acrylate-based layers. Next, a layer of a relatively transparent, fluid material is applied on the adhesive agent, wherein said material can flow into the dead spaces in the undercuts, and can fill these in. It must be ensured in the process that the material cures sufficiently in this space. Next, one or more layers of opaque material can be applied on this fluid layer, to conceal the subframe with color. The actual veneer composite then forms the completion of the layered construction.
WO 2008113541A2 relates to conditioning agents which are suitable for polymers selected from the group containing polyarylates, polyarylene sulfides, polysulphones, liquid crystal polymers, polyimides, polyether imides, polyamide imides, and polyaryl ether ketones. The conditioning agents contain an adhesive and a higher boiling point solvent with dipole character, the latter selected from the group containing dimethyl sulfoxide, phenol, diphenyl sulfone, cyclohexanone, acetyl acetone, and ethylene glycol. The use thereof comprises the application of the conditioning agent onto at least a part of the surface of the mold body, allowing the conditioning agent to work in, and optionally applying a curable mixture onto the surface of the mold body conditioned by means of the conditioning agent. The examples relate to DMSO-containing conditioning agents. DMSO is not without problems according to the safety data sheet thereof, and is not suitable for use in the mouth1: 1 product name: dimethylsulfoxide (DMSO)